`@lezer/generator` is incorrectly built

Getting this error in my rollup build:

[!] Error: 
    Directory import '<repo>/node_modules/.pnpm/@lezer+generator@1.4.2/node_modules/@lezer/generator/' 
    is not supported resolving ES modules 
    imported from <repo>/node_modules/.pnpm/@lezer+generator@1.4.2/node_modules/@lezer/generator/dist/rollup-plugin-lezer.js

and looking at the current version on npm,

it does look like @lezer/generator is published with an assumption on some specific build configuration – which isn’t safe.

But also, importing from .. within the dist directory means above the dist directory, and there are no js files to import there.

Pinning to 1.4.0 unblocks anyone running in to this.

This patch should help.

Confirmed, thanks!